Variegated tissue paper coloring apparatus

ABSTRACT

A METHOD OF AND APPARATUS FOR DYEING A WEB OF PAPER, PARTICULARLY TISSUE PAPER, INTO PRIMARY BANDS OF DIFFERENT, BRILLIANT, DISCRETE, COLORS EXTENDING LONGITUDINALLY OF THE WEB WHICH ARE SEPARATED BY SECONDARY BANDS ALSO EXTENDING LON-   GITUDINALLY OF THE WEB IN WHICH ADJACENT PRIMARY BAND COLORS ARE SOFTLY BLENDED ONE WITH THE OTHER.

United States Patent Leo Fleischer Cincinnati. Ohio 1 2| 1 Appl. No. 869.965

[22] Filed Oct. 27. 1969 Division of Ser. No. 810.900, Feb. [7, I969. Pat. No. 3.512.914. and a continuationlit-part 0! 422.838, Dec. 31,1964, now

abandoned Continuation of application Ser. No. 257.109. Feb. 13, 1963, now abandoned.

[45] Patented June 28. 1971 (73] Aaeignee Crystal 'l'laaae Company Mlddletowa, Ohio [72] Inventor (54] VARIEGATED TISSUE PAPER COLORING APPARATUS 4 Clalls, 2 Drawing Figs.

[52! U.S.Cl. 118/115, ll8/ll7.ll8/4l2,ll8/4l5 [SI] lnt.Cl ..B05c 11/02, BOSc 3/00 [50] Field 0! Search 1 18/407, 410, 41 l,4l2.4l3,4l4,4l5, 1 l5, 1 17; 68/205 [56] References Cited UNITED STATES PATENTS 1,944.835 1/1934 Boyers l18/415X 2,766,717 10/1956 Neidich et al..- 1l8/4lSX Primary Examiner.lohn P. McIntosh ABSTRACT: A method of and apparatus for dyeing a web of paper, particularly tissue paper, into primary bands of differcnt, brilliant, discrete colors extending longitudinally of the web which are separated by secondary bands also extending longitudinally of the web in which adjacent primary band colors are softly blended one with the other.

PATENTED JUN28197I INVENTOR. 4% 4M WW VARIEGATED TISSUE PAPER COLORING APPARATUS This application is a divisional of U.S. application Ser. No. 810,900, filed Feb. 17, 1969 (now U.S. Pat. No. 3,512,914). U.S. application Ser. No. 810,900, filed Feb. 17, 1969 is a continuation-in-part of U.S. application Ser. No. 422,838, filed Dec. 31, 1964, now abandoned. U.S. application Ser. No. 422,838, filedDec. 31, 1964, is a continuation of U.S. application Ser. No. 257,189, filed Feb. 8, 1963, now abandoned.

' This invention is particularly directed to a uniquely and very pleasingly colored tissue paper, a method of applying a number of differently colored dyes to create that colored tissue paper, and apparatus for carrying out the method to achieve the end product.

1n Franz, U.S. Pat. No. 1,548,261, there is disclosed a method of,and apparatus for producing colored effects upon paper and fabrics by flowing a plurality of streams of dif ferently colored liquids down an inclined surface into a nip created by a pair of opposed surfaces pressured one against the other, thereby forming a pool of different colored liquids in that nip. Presumably the different streams intermix to a limited extent as they flow toward the nip. A web of paper or fabric is then passed through the pool to color the web; therefore, the different colored liquids are contacted with the web as the web passes through the nip between the two opposed pressure surfaces. Different apparatus for applying this colored effect are shown in each of H68. 1-5 of this patent, but in each case the colored effect is not imparted to the paper or fabric web until that web passes through the colored liquid pool in the nip created by two opposed surfaces pressured one against the other.

Franz also discloses that positive intermixing of the liquids deposited on the inclined surface (whether that surface be a plane A, or a roll C, or an endless band B), may be provided by scrapers, or oscillating or rotating bodies," see page 1, lines 4647, prior to the liquids reaching the nip to form the liquid pool. That is, such mixing occurs'upstreamfrom the nip created between the, two opposed surfaces pressured one against the other but, in all cases, the web is still not colored until it reaches .the pool formed in that nip. Further, Franz discloses that by acting with compressed air or with a stream of water on the solution collected between the rollers, see page 1, lines 4345, positive intermixing of the liquids at the nip itself, instead of upstream therefrom, may occur.

Without such positive and preliminary mixing operations as vaguely disclosed in Franz, that is, by simply flowing the dyes on an inclined surface toward the nip, it has been my experience that intermixing of the different colored dyes does not occur to a sufficient extent to permit creation of a tissue paper having brilliant, different colored primary bands separated by relatively wide, color intermixed, secondary bands that are softly blended of those colors from which the adjacent primary bands are formed such as is achieved by the method and apparatus of my invention. Further, such a preliminary mixing operation in the manner incidentally sugg'ested by Franz, whether carried out at the nip of the two opposed surfaces pressured against one another or upstream of the nip on one of those surfaces, is a relatively difficult operation to control with any reasonable degree of success because of the relatively small volumes of liquid solutions involved. However, with the method and apparatus of my invention, product reproducibility is relatively easily maintained and the blending of the primary band colors into relatively wide, soft, secondary band colors proceeds without the necessity of air pressure sources, water sources, or complex rotating or oscillating bodies such as is disclosed for intermixing purposes in Franz. Further, no soft or washed appearance for the secondary band colors results when the Franz method is used.

In Cadgene, U.S. Pat. 1,773,169, a process is disclosed in which a cloth fabric is colored as it passes through a pool of dyes created at the nip of two felt covered pressure rolls. Here, as in Franz, the pool of dyes is created at the nip of two upposed surfaces pressured one against the other, the fabric receiving its coloration only as it passes through the nip formed by those two opposed surfaces. In Neden,.U.S Pat. No. ,1 ,308,098, there is disclosed a method of coloring a fvveb of paper by also passing the web between two opposed surfaces pressured one against the other, one of whichslipsrelative to the other so that the differently colored liquidsfpooled at the nip impart colorant to the web as it passes throughthe nip. ln Angier et al., U.S. Pat. No. 1,882,714, there is di s' closed a method and apparatus for coloring sheet material that also involves the creation of a pool of colorant at the nip of two opposed surfaces pressured against one another. The web is passed through the nip and the colorant imparted at that point. While the patent does state that the coloring material may be applied to the web in advance of the line of contact at the bite of the roll," see page 1, lines 36--38, it goes on to qualify this statement by saying that it must be discharged on one or more of the... where they converge to form the trough as they pass through the nip of the pressure rolls, page 1, lines 39-49. Such a procedure is illustrated in FIG. 1. In none of these references is there disclosed methodsteps or apparatus for achieving relatively wide secondary .bands having a washed or soft appearance while retaining-the brilliance of the primary band colors. Further, the width bflthe blended or secondary color bands formed by these {methods is minimal compared to those widths that can be achieved by my method and apparatus. Y

Experimentation and, recently, prolonged runs on a commercial basis, have shown that the providing of different colored primary bands and the ,blending of adjacent primary band colors into secondary band colors achieved by running a web of dye absorbent paper, particularly tissue paper, through a puddle of different colored dyes created at the nip between two opposed surfaces pressured against one another (such as between two pressure rolls), as disclosed in all of the prior art, does not produce a paper having the brilliance in the primary bands of discrete colors and the softness in the secondary bands of blended colors, nor the width of the secondary bands, that is obtained by the method and apparatus herein disclosed.

The present invention is generally related to the same area of the art of the above four patents, but it is specifically directed to the problems attendant the production ofcolored webs of dye absorbent paperlike tissueipaper that bear uniquely brilliant, different colored primary bands and that are separated one fromthe other by secondary bands of. soft colors blendedfrom the adjacent brilliant colored bands not obtainable by any other method or apparatus disclosed in the prior art noted above. The preferred end product of this invention is a web of tissue paper having a number of longitudinally extending primary bands of brilliant, discrete colors separated by areas or secondary bands in which the colors of adjacent primary bands are softly blended one with the other. In the method of and by the apparatus of this invention, the blending of adjacent primary band colors into secondary bands gives an unusual, soft, washed appearance to those secondary bands similar to that of a Madras" cloth after repeated washings. One of the unique features of the method and apparatus of this invention is the retention of the brilliance of the individual colors in the primary bands while yet providing soft, washed secondary bands between the primary bands. Thus, it is toward the problem of retaining the brilliance of the colors in the primary bands, as well as creating and controlling the soft blend in the secondary bands, that the method and apparatus of the present invention is directed.

Otherwise expressed, the objective of this invention has been to provide a method of and apparatus for producing a web of dye absorbent paper such astissue paper having multicolored primary bands of brilliant discrete colors separated by secondary bands in which adjacent primary band colors are controllably and reproducibly blended into a soft or washed blend without muddying or clouding the colors of the primary hands.

Other objectives and advantages will be more apparent from the following detailed description in conjunction with the drawings in which:

FIG. 1 isa diagrammatic perspective view showing a web of tissue paper being treated in accordance with the method and apparatus of this invention, and

FIG. 2 is an enlarged cross-sectional view taken on the line 2-2 of FIG. 1.

In the drawings, the numeral refers generally to 'a web of tissue paper. Preferably this web is a tissue paper having wet strength characteristics so that it can withstand being impregnated by liquid dye solutions without breaking. However, heavier weight papers may be used as long as they are characterizedby. the ability to quite rapidly absorb dyes to give even dye impregnation of the web such as is achieved with tissue paper. The web moves from left to right as viewed in H0. 1, and coming from a supply roll at the left (not shown) it passes first over a guide roll 11 that is free to rotate with the moving web. The web then passes underneath a cylindrical spreader bar 12 preferably fixed in position against rotation. Note that no supporting surface is present underneath the fixed spreader bar 12. That is, there is no belt, roll or the like that is pressured against the spreader bar 12 to create the nip through which the web must pass. From the fixed spreader 12 the web passes over the first one of two pressure rolls," designated 13 and 14 respectively. The web then passes down through the nip between rolls l3 and 14. The pressure rolls l3, 14 preferably are horizontally aligned, that is, the axes of each roll 13, 14 are located in the same horizontal plane, to permit creation and use-of a continuously changing or flushing pool of wash water 36 in the nip. Fromthe pressure rolls, 13, 14 the web goes to a conventional dryer, not shown, and from thence to a windup roll, not shown. Neither the dryer nor the windup roll are shown because they are of conventional design, being similar to those used in conventional staining processes for tissue paper wherein a single color is used to stain the entire web.

In the embodiment shown, five differentlycolored dyes are employed to stain the web of tissue paper in five discrete longitudinal bands designated 15 through 19 respectively. These different dyes are contained in individual containers designated 20 through 24 respectively. These containers may be conveniently mounted somewhere above the run of tissue paper so that the dyes feed down toward the web by gravity, the, specific design of the containers being unimportant to the method and apparatus of this invention. Individual outlet pipes, designated 25 through 29 respectively, lead from the individual containers 20-24, the flow from the individual containers into-the individual pipes being adjustable and controllable by means'of valves designated 30 through 34 respectively.

It is preferred that the lower end of each one of the pipes 25-29 terminatesat a point closely adjacent to the surfaces of the cylindrical spreader 12 so that the dye solutions are deposited on the spreader bar 12. It is to be noted that in each instance of the pipes 25-29 the lower end of a pipe terminates such that the dye flows onto the fixed cylindrical spreader 12 at a point that is removed from the top center thereof toward the direction of the oncoming web 10 by an amount that places the effiuent stream of dye between 15 to 40 off the top center of the cylindrical spreader. Further, as shown in FIG. 1', the individual pipes 25-29 are placed sufficiently close together that the effluent dyes run down the side of the fixed cylindrical spreader to merge in a pool or puddle 35 that accumulates between the web of tissue paper and fixed cylindrical spreader 12. The dyes could be deposited directly onto the web upstream of the spreader bar 12 although this is not preferred. The puddle 35 is composed of pure, undiluted dye. in those areas of the puddle 35 between adjacent dyes the dyes are unexpectedly found to substantially blend or intermix as the tissue web passes underneath the spreader bar 12 and as the blend is deposited on or impregnated into the web. Note that no. surface in the form of a belt, roll. or the like is provided to exert pressure against-the spreader bar 12 and, hence, no nip formed by opposed surfaces pressured against one another is created through which the web must pass as it receives'the dye. This method step and apparatus arrangement admits of close control of the widths ofthecprimary and secon-.

dary color bands, permits relatively broad secondary color bands to be achieved, permits rapid dye impregnation of the paper, and provides even and thorough dye impregnation cgfr-- oscillating or rotating apparatus to mix the dyes preliminary to.

or simultaneous with their contacting the web for dyeing pur- 1 poses. This relationship is best shown in P16. 2. Thus, a pool 35 of the different dye solutions is formed in the upstream nip 1 created by the spreader bar 12 and the web 10, the wide secondary blended bands as well as the primary discrete bands of different colors being imparted to the web at this point.

While the spreader 12 could be mounted for rotation it is preferably fixed in place because it has been found that a smaller volume of dye is needed to stain a given web lengtha particular shade of a color when the spreader 12 is fixed in place as opposed to when it is permitted to rotate. Further, in comparison with the diameters of the pressure rolls 13 and 14 the diameter of the fixed cylindrical spreader 12 is rather small. It is preferred the diameter be as small as possible to cut down on the drag created between the wet web of tissue paper and the spreader 12. However, the lower limit on the diameter of the spreader 12 is usually limited by the fact that it must maintain its rigidity without bowing during use.

It may be noted that the web 10 travels upwardly in passing from the underside of the fixed cylindrical spreader 12 to the top of pressure roll 13. It may also be seen that the web passes relatively downwardly from the top of the guide roll 11 to the underside of the fixed cylindrical spreader 12. This leaves the underside of the fixed cylindrical spreader 12 as a low point between the top of guide roll 11 and the top of the pressure roll 13. Otherwise expressed, the web 10 of tissue paper does not move in a straight path from'guide roll 11 to the top of pressure roll 13 but instead it is depressed between them. Hence, the dyes are applied to the web 10 while it is under tension and held snugly against the underside of the spreader 12, thereby permitting the pool 35 of dyes upstream of the spreader bar to be established.

As the tissue web leaves the fixed cylindrical spreader l2 and passes toward the first of the two pressure rolls 13, 14 there is a run of appreciable length in which the undiluted or pure dyes are permitted an opportunity to further blend one with the other in those secondary bands adjacent different pri mary bands and to completely and evenly impregnate the web. Hence, by the term appreciable or extended length of run is meant a distance sufficient to allow the dyes to evenly and completely saturate the paper; it will be apparent to those skilled in the art that such a distance will vary depending on the type and quality of dye absorbent paper used and the type of quality of the dyes used.

A water flush or web wash is provided at the nip of rolls 13, 14 which is created by the constantly flowing wash water 36. Any excess of dye imparted to the web 10 by the dye pool 35 at the spreader bar 12 is removed at the pressure rolls l3, 14, which rolls essentially function-to squeeze out the excess dye. If such squeezings are not flushed from the nip of the pres sure rolls l3, 14 a pool of completely intermixed dyes forms which impairs the brilliance of the primary band colors. Further, such a water flush atthe nip' causesthe secondary bands of blended colors to take on a very pleasing'soft or washed appearance, thereby creating the Madras" effectin the overall appearance of the finished dyed web. Thus, the effect of brilliant primary color bandsseparated by soft secondary color bands is promoted by (a) the actual fading of those secondary bands due to the squeezing out of dye by the pressure rolls l3, l4 and the washing of those areas by the continuous flush of wash water 36, and (b) the retaining of brilliance in the primary color bands by the constant flow of water stream 37 through the nip of pressure rolls l3, 14 to remove continuously the dye solution squeezed out by the pressure rolls 13, 14 which would impair or dull the primary color bands if left unremoved. It is not fully understood why the pressure roll nip and the water flush tends not to wash out or soften the brilliance of the colors in the primary bands l5 through 19 of the web, or why it tends to add to the fading of the colors in the secondary bands.

Pipe 38 used to provide the stream 37 of water that is fed into the nip between rolls [3 and 14 preferably is positioned to discharge the stream of water at a point roughly halfway between the two ends of the rolls l3 and 14. The stream is of such a volume that it has a highly diluting effect upon the dyes that would otherwise accumulate within the nip between rolls l3 and 14 to wash or flush thoroughly those dyes from the nip. in the preferred practice of the invention there is a steady, substantial flow of water and mixed dyes from both ends of the pool in the nip between the pressure rolls 13 and 14.

As to the dyes utilized in the method apparatus of this invention, they may bethose normally used in an operation wherein a web of tissue paper is stained all one color. It is recommended that the dyes used be either all basic or all acidic so that no reaction occurs between the dyes which might result in a precipitation in those areas in which adjacent colors intermix or blend. Further, the dyes utilized preferably are of the type that penetrate completely through the web as quickly as possible upon initial wetting so that opposite sides carry identical colors just as in a conventional single color staining operation. One main consideration is that the pure undiluted dyes remain upon the web during that part of the run shown in between the spreader bar 12 and the pressure rolls l3, l4, and that this run be sufficiently long for the individual colors to have an opportunity to completely saturate the web of tissue paper prior to passing through the nip of pressure rolls l3, l4 and the water flush that exists at this pressure roll nip.

Having described the preferred embodiments of my invention,

lclaim:

1. Apparatus for coloring a web of dye absorbent material comprising a spreader bar positioned to exert downward pressure on said dye absorbent web, there being nofurther surface positioned below said spreader bar to exert an upward pressure against said dye absorbent web dye source means adapted to cooperate with said spreader bar and positioned to direct a plurality of different colored dye solutions onto said dye absorbent web a set of pressure rolls positioned to allow said dye absorbent web to pass through the nip of said pressure rolls, said rolls being located downstream to said spreader bar an extended distance sufficient to permit said dyes to completely saturate said dye absorbent web, and

fluid source means adapted to cooperate with said pressure rolls and positioned to direct a flushing volume of fluid into the nip of said pressure rolls to highly dilute dye solutions accumulating therein, said rolls being structured to permit the fluid to run free from the ends of the nip.

2. Apparatus as set forth in claim 1 wherein said dye source means directs said dye solutions onto said web in a manner that creates a single liquid pool of dyes in the upstream nip formed between said dye absorbent web and said spreader bar, thereby providing apparatus for coloring the dye absorbent web with primary bands of difierent discrete colors separated by secondary bands of blended colors, the blended colors being blends of adjacent primary band colors.

3. Apparatus as set forth in claim 2 wherein the axes of said pressure rolls are positioned in the same substantially horizontal plane.

4. Apparatus as set forth in claim 2 wherein said dye source means directs the plurality of different colored dye streams onto said spreader bar at spaced points along its length so that said dyes run from said spreader bar onto said web. 

